As a fellow early 2013 MBP owner (15"), I was wondering about this as well and I can assure you that we'll be comfy till at least 2022.
Here's my reasoning:
We'll be getting macOS 10.15, so even if Apple decides to cut off support for our Macs when 10.16 comes out, it means we'll still be getting 2 more years of security updates. So unless they introduce some sort of killer feature that we desperately need, we won't have to buy new Macs in order to be safe and sound till late 2022.
Now, I said "even if" because I don't think Apple will drop us with 10.16 but with 10.17. In that case we still have 4 more years, till 2023.
This is based on Apple's ~7 years of support policy when it comes to Macs. It's not set in stone, but it's a very good indicator.
As for the future, I'm cautiously optimistic:
- Intel expects Apple to drop them and ship their own ARM based Mac in 2020 or 2021. They will probably switch over MacBooks first, and desktops later.
- Apple's working on "redesigning the redesign" (LOL) of their keyboards by returning to a scissor-based mechanism.
- Apple has lowered a few prices here and there with their new Mac lineup. In the case of the MBA's lower price tag, they give even more value by making the display True Tone!
I hope they'll also realize MagSafe needs to come back, include more ports, and as the icing on the cake bring back the illuminated Apple logo ^^
Don't hold your breath for those though.
So by the time we need to go shopping for a new MacBook, it's very possible that we'll find ourselves in the 5th gen of MacBooks. Having dodged the bullet that was the 4th gen
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Btw, as I was typing this post I realized that we're kind of in a luxury situation. Our MBPs aren't defect (yet) so getting no more software support can leave you thinking "but this machine still works fine, just give me those new software features!" which is very understandable. It's an issue people with broken laptops don't have LOL
Now, you don't have to follow Apple's official support policy though. There are quite a few threads of people running 10.14 just fine on no longer supported hardware for example.
Or you can also put Linux on it and get at least another 6y out of the machine (full OS updates, not merely security updates!), although that may not be an option depending on how heavily invested you are into Apple's ecosystem.
Cheers
